The present invention relates to a golf ball composed of a core and one or more cover layer. More specifically, the invention relates to a golf ball with a distinctive appearance that has a visual impact on the golfer.
Most solid golf balls have a surface color which is typically white. However, manufacturers have been placing greater emphasis lately on consumer individuality and fashionability by producing different types of colored golf balls and golf balls containing a variety of pigments.
In such solid golf balls, a cover layer which covers the surface of the solid core, particularly an outermost cover layer situated on the outermost side of the cover layer, contains various color pigments, aluminum flakes and pearlescent pigments, thus imparting color or brightness to the surface of the ball. The purpose, of course, is to supply golfers with balls having this type of distinctive and aesthetically pleasing appearance.
An example of such a golf ball is the solid golf ball described in JP-A 2001-87423.
However, in the foregoing prior art, when a cover material containing aluminum flake pigment or pearlescent pigment is injection molded, weld lines generally arise in the direction of flow by the base resin. Such weld lines change the orientation of the pigment. This, together with the large aspect ratio of the pigment, alters the manner in which the pigment is perceived, compromising the uniformity of the ball's appearance.
JP-A 2004-166719 (and corresponding U.S. Pat. No. 6,824,479) disclose, with regard to marks such as lettering or a play number formed on the surface of a golf ball, the formation over the marks and their immediate vicinity of a clear coat which contains a luster material composed of glass flakes coated on the surface with a metal oxide. However, because this prior-art invention imparts brightness only to the area of the marks and does not provide the entire surface of the ball with a distinctive appearance, the ball has only a modest visual impact (novelty).